Desalination Plant Intakes - WateReuse Association

critical period of their development (i.e., after their yolk sack is empty). All of these forces haveseveral orders of magnitude higher impact on fish populations than seawater intakes.Source: Tenera EnvironmentalFigure 5 – Typical Reproduction and Survival of Larval Producing OrganismsFor example, a single female halibut produces as many as 50 million eggs per year for as long as20 years, or one billion eggs over a lifetime 7 . In simple terms, the annual entrainment impact ofone 50 MGD desalination plant would be comparable to the annual bio-productivity of fiveadult female halibut fish (i.e., the “environmental impact” which five fishermen can cause withtheir daily halibut catch quota of one fish each).The environmental impact of desalination plant operations should be assessed in the context ofthe environmental impacts of water supply alternatives that may be used instead of desalination.Desalination projects are typically driven by the limited availability of alternative lower-costwater supply resources such as groundwater or fresh surface water (rivers, lakes, etc.). However,damaging long-term environmental impacts may also result from continued over-depletion ofthose conventional water supplies, including inter-basin water transfers. For example, overpumpingof fresh water aquifers over the years in a number of areas worldwide (i.e., the SanFrancisco Bay Delta in Northern California; wetlands in the Tampa Bay region of Florida; andfresh water aquifers, and rivers and lakes in northern Israel and Spain, which supply water tosustain agricultural and urban centers in the southern regions of these countries), has resulted insubstantial environmental impacts to the traditional fresh water resources in these regions. One7 http://www.watereuse.org/sites/default/files/u8/Quote%207%20-%20Presentation.pdfSeawater Desalination Plant Intakes – Impingement and Entrainment Page 6